VESSEL TRACKING

Vessel is the most valuable tangible asset for every shipping company. Frequent monitoring and accurate information regarding location / condition of the vessel during voyage is very essential to ensure smooth voyage and timely delivery of the cargo.

Daily report from ship side conveyed through email and communication through satellite phone between ship and shore staff. Shore staff basically will rely upon daily report from vessel side.

But, what if all communication line down due to hardware problem (ship radar broken due to rough weather) or poor signal? How to know the exact location of the ship? How far it is from the port of destination?
In emergency case, what safety measure or emergency response to be done?

About AIS, LRIT and VT service
To answer above questions, starting in 2002 all new commercial ships over 300 gross tons, and all new passenger vessels, are required to include AIS transponders. The requirement for existing ships has been gradually phased in.

The AIS System transmits information encoded on two VHF channels, at 161.975 Mhz, 162.025 Mhz. Typical range is between 20 and 50 nautical miles.
The AIS transponder receives information from the ship’s other navigational instruments. Position, course, and speed over ground information is typically provided by a GPS receiver.

Ships that are moored or at anchor are required to transmit their position information at least every 3 minutes. Ships moving at up to 14 kts must transmit their position every 10 seconds; at up to 23 kts, every 6 seconds; and at faster speeds, every 2 seconds.

The ship’s officers must enter information such as ship name, ship type, ship dimensions, and estimated time of arrival. This information is not always entered correctly and is sometimes out of date, which accounts for the peculiar information.
In addition, static information (such as the ship’s name, destination, and estimated time of arrival) is transmitted separately every 6 minutes.

Besides AIS, we also have LRIT ( Long Range Identification and Tracking). This system was established as an international system on 19 May 2006. LRIT regulation applies for ship that engaged on international voyages.

Ships must automatically report their position to their Flag Administration at least 4 times a day. Every sovereign nation already has the right to request such information for ships destined to their ports. Hence, this LRIT data serve as vessel traffic database.

Now, let’s jump into what is VT all about…
VT is one step further than AIS and LRIT. It provides a graphic display of AIS targets onto electronic charts. The application retrieves AIS tracking data on regular time intervals and displays the vessel positions.

In short, VT is a combination between vessel data (AIS) and vessel traffic data (LRIT). For further understanding, below scheme might be useful:

AIS Network -> Internet -> AIS server -> Vessel Traffic Database -> Data dispatcher -> VT Explorer users

Brief explanation re user of this VT services:
• Owner / operators track their own fleet and their competitor’s movement
• Oil major and ship manager use movements for vetting
• Cargo consignees track vessel position
• Underwriters track vessel to profile risk and set up insurance premiums
• Environmental and regulatory organizations to determine which vessel was responsible for an environmental incident
• Engine manufacturers track vessels for their engine performance versus their competitors
• Ship brokers track vessel to obtain movements data
• Lawyers to arrest vessel should any dispute or legal matter arise
• Suppliers at ports track inbound vessel movements to market their services
• Analysts to analyze the global trading patterns